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The Scientific

Method involves a series of steps that

are used to investigate a

natural occurrence.

We shall take a

closer look at these steps and the terminology you will need to

understand before you start

a science project.

1. Problem/Question 2. Observation/Research

3. Formulate a Hypothesis 4. Design and Perform Experiment

5. Collect and Analyze Results 6. Conclusion

7. Communicate the Results

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Steps of the Scientific Method

1. Problem/Question: Develop a question or problem that can

be solved through experimentation.

Steps of the Scientific Method

2. Observation/Research: Make observations and research

your topic of interest.

Do you remember the next step?

Steps of the Scientific Method

3. Formulate a Hypothesis: Predict a possible answer to

the problem or question. Example: If soil temperatures

rise, then plant growth will increase.

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Steps of the Scientific Method

4. Experiment: Develop and follow a procedure.

Include a detailed materials list. The outcome must be

measurable (quantifiable).

Steps of the Scientific Method

5. Collect and Analyze Results: Modify the procedure if

needed. Confirm the results by retesting.

Include tables, graphs, and photographs.

Steps of the Scientific Method 6. Conclusion: Include a statement that accepts or

rejects the hypothesis. Make recommendations for

further study and possible improvements to the

procedure.

Steps of the Scientific Method

7. Communicate the Results: Be prepared to present the project

to an audience. Expect questions from the

audience.

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Think you can name all seven steps?

Problem/Question Observation/Research Formulate a Hypothesis Experiment Collect and Analyze Results Conclusion Communicate the Results

Let’s put our knowledge of the Scientific Method to a realistic example that includes some of

the terms you’ll be needing to use and understand.

Problem/Question John watches his grandmother bake bread. He ask his grandmother what

makes the bread rise.

She explains that yeast releases a gas as it feeds on sugar.

Problem/Question

John wonders if

the amount of sugar used in the recipe will affect the size of the

bread loaf?

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Caution! Be careful how you use effect and

affect.

Effect is usually a noun and affect, a verb.

“ The effect of sugar amounts on the rising of bread.”

“How does sugar affect the rising of bread?”

Observation/Research

John researches the areas of baking and

fermentation and tries to come up with a way

to test his question. He keeps all of his information on this topic in a journal.

Vocabulary check

John talks with his teacher and she

gives him a Experimental

Design Diagram to help him set up his investigation.

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Formulate a Hypothesis After talking with his

teacher and conducting further

research, he comes up with a hypothesis.

“If more sugar is added, then the bread will rise

higher.”

Hypothesis The hypothesis is an educated

guess about the relationship between the independent and

dependent variables.

“If more sugar is added, then the bread will rise higher.”

Do you know the difference between the

independent and dependent variables?

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Independent Variable The independent, or manipulated

variable, is a factor that’s intentionally varied by the

experimenter.

John is going to use 25g., 50g., 100g., 250g., 500g. of sugar in

his experiment.

Dependent Variable The dependent, or responding variable, is the factor that may change as a result of changes

made in the independent variable.

In this case, it would be the size of the loaf of bread.

Experiment

His teacher helps him come up with a

procedure and list of needed materials.

She discusses with John how to determine

the control group.

Control Group In a scientific experiment, the

control is the group that serves as the standard of comparison.

The control group may be a “no treatment" or an “experimenter

selected” group.

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Control Group The control group is exposed to the

same conditions as the experimental group, except for the

variable being tested. All experiments should have a

control group.

Control Group Because his grandmother always used 50g. of sugar in her recipe, John is going to use that amount in his

control group.

Constants John’s teacher

reminds him to keep all other factors the same so that any

observed changes in the bread can be attributed to the variation in the

amount of sugar.

Constants

The constants in an

experiment are all the factors that the

experimenter attempts to keep

the same.

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Can you think of some constants for this

experiment?

Constants They might include:

Other ingredients to the bread recipe, oven

used, rise time, brand of ingredients, cooking time, type of pan used,

air temperature and humidity where the

bread was rising, oven temperature, age of

the yeast…

Experiment John writes out his

procedure for his experiment along

with a materials list in his journal. He has

both of these checked by his

teacher where she checks for any safety

concerns.

Trials Trials refer to

replicate groups that are exposed

to the same conditions in an

experiment. John is going to test

each sugar variable 3 times.

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Trials

•  How many loaves of bread will John bake?

3 Trial with different variables

X 5 different variable ___________________________________________________

15 Trials

Collect and Analyze Results

John comes up with a table he can use to record his data. John gets all his materials together and carries out his

experiment.

Size of Baked Bread (LxWxH)

Amt. of Sugar (g.)

1 2 3 Average Size (cm3)

25 768 744 761 758

50 1296 1188 1296 1260

100 1188 1080 1080 1116

250 672 576 588 612

500 432 504 360 432

Size of Bread Loaf (cm3)

Trials

Control group

Collect and Analyze Results John examines his data and notices that his control worked

the best in this experiment, but not significantly better

than 100g. of sugar.

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Conclusion John rejects his hypothesis, but

decides to re-test using sugar

amounts between 50g. and 100g.

Experiment

Once again, John gathers his

materials and carries out his experiment.

Here are the results.

Can you tell which group did the best?

Size of Baked Bread (LxWxH) cm3

Amt. of Sugar (g.)

1 2 3 Average Size (cm3)

50 1296 1440 1296 1344

60 1404 1296 1440 1380

70 1638 1638 1560 1612

80 1404 1296 1296 1332

90 1080 1200 972 1084

Size of Bread Loaf (cm3)

Trials

Control group

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Conclusion John finds that

70g. of sugar produces the largest loaf.

His hypothesis is accepted.

Communicate the Results

John tells his grandmother about

his findings and prepares to present

his project in Science class.

Vocabulary check